Tracing the evolution of Manny Pacquiao's fighting style is a case study in metamorphosis. 

Pacquiao, the fighting pride of the Philippines, is one of the best fighters who has ever lived. He’s won legitimate alphabet titles in eight different weight classes and lineal championships in four. He’s one of the most popular superstars in boxing history and will be honored by future historians as one of the most accomplished fighters of his or any other generation.

The southpaw will be in the biggest fight of his professional career when he takes on Floyd Mayweather on May 2 at the MGM Grand in Las Vegas. It is being hailed as the biggest fight in boxing history.

Pacquiao’s true greatness, the thing that separates him from his contemporaries and gives him a solid chance to be the first to defeat Mayweather, is defined by how hard he has toiled behind closed doors to hone his craft through each stage of his illustrious career.

His evolution as a prizefighter was no accident.

It is perhaps overly simplistic, but for brevity’s sake, as well as the paradigm from which it is to be dissected, there have been three different Pacquiaos, each one more formidable than the prior in his own way.

The first Pacquiao the world saw was a one-handed wrecking ball. This version of Pacquiao relied on equal parts speed and power, particularly that supplied by his straight left hand.

It was good enough to net Pac-Man titles at flyweight and junior featherweight and to dominate Mexican legend Marco Antonio Barrera, but he ultimately failed against other elite-level foes such as Juan Manuel Marquez and Erik Morales. 

Pacquiao knocked Marquez down three times in their first encounter back in 2004 but was outboxed the rest of the way for a draw. Morales outfought Pacquiao over 12 rounds a year later for the WBC junior lightweight strap.

Pacquiao’s simple punching patterns at the time were bolstered by his incredible speed and power. While he was overly reckless and aggressive, his athleticism and ability to land punches from distances not typically seen allowed him to blitz his opponents into oblivion before most even understood what was happening.

And defense was of minimal concern. Pacquiao’s offense was so devastating that his defensive liabilities remained mostly hidden behind blindingly fast hands and the force of which he landed his thudding punches.

Pacquiao’s opponents were so busy fending off the buzz saw that opportunities for counter-aggression were minimized. Besides, it’s hard to land punches as you’re getting whacked around the ring like a pinball.

But Pacquiao and trainer Freddie Roach did not rest on his God-given attributes. In fact, according to Lance Pugmire of the Los Angeles Times, Roach went so far as to apologize to Pacquiao after the Morales loss in 2005 for not helping the dynamite slugger develop a more competent right hand.

The second Pacquiao then emerged.

Pacquiao and Roach clearly improved the fighter’s right-handed power and in short order. It worked well enough to avenge the Morales loss twice, both by knockout, and was the primary reason the former flyweight was able to make mincemeat of Hall of Fame-caliber welterweights from 2009-12.

Case in point, Pacquiao’s 2009 lightweight title win over David Diaz was punctuated with whelps and bruises caused by the newly powerful right hand.

Overall, this second version of Pacquiao is the fighting Filipino boxing fans witnessed from 2005 to 2012. Pacquiao’s success wasn’t only about the right hand, though. His offense developed more complex punching patterns, and he augmented his frenetic style with an improved defense as well.

The second Pacquiao was equally destructive with his right and left hands. His defense improved greatly, aided mostly by improvements in footwork, recognition of proper entry and exit angles and an increased ability to block and parry return fire with his arms and hands.

There are many who point to this version of Pacquiao as the fighter’s peak. Their argument is that this version of Pacquiao was the best offensively and good enough on defense to give anyone fits. It’s an idea not without merit.

Between 2008 and 2012, Pacquiao dominated naturally larger foes including Oscar De La Hoya, Ricky Hatton, Miguel Cotto, Antonio Margarito and Shane Mosley. Moreover, Pacquiao picked up two close wins over his great counterpunching rival, Marquez, and arguably defeated Timothy Bradley in their first bout, despite the egregious scorecards turned in by judges that gave Bradley the official nod.

But this version of Pacquiao was open to counterpunches from risk-takers, men willing to stand in the pocket as Pacquiao unleashed his arsenal of power punches in high volume. Subsequently, Marquez knocked out this version of Pacquiao during the fourth fight of their series in December 2012.

But a third Pacquiao rose from the ashes. Since the devastating loss to Marquez, Pacquiao has molded himself into perhaps the most formidable version yet. While the spectacular knockout wins have gone by the wayside, this version of Pacquiao just might be the most difficult to defeat.

Pacquiao is still a two-handed fighter. He has not regressed to the one-handed menace he was for the first 10 years of his career. And Pacquiao’s punching patterns have remained complicated enough to keep opponents from honing in on easy counters.

In short, the improvement he and Roach perfected after the loss to Morales are still present.

But this version of Pacquiao relies more on his speed than his power. He uses his jab better now than at any other time in his career, and he gauges distance better, too.

The primary difference between the latest version of Pacquiao and the previous is his conscious effort to not overcommit on offense. He notes where his feet are placed at almost all times in a fight, uses his front hand as a rangefinder and makes conscious efforts to step back from his opponents to stay outside of power-punching range.

Moreover, Pacquiao keeps his arms and hands in a guarded position more than at any other time of his career, and he does not take unnecessary risks.

Version No. 3 of Pacquiao is precisely the one that can give Mayweather problems. He is the epitome of controlled aggression. He is no longer a cinch to counter, and he will not rev up his offense for mere style points.

Pacquiao is the type of fighter now content to rely on hand speed and volume punching, even when it is quite apparent he does not have to do so. He is patient.

Look no further than two of Pacquiao’s last three wins as evidence. Against Brandon Rios in 2013 and Chris Algieri in 2014, it was quite apparent that Pacquiao could land punches at will. Against Algieri, he went so far as to floor the 140-pound titlist six times over the course of 12 rounds.

Pacquiao is now a complete fighter. He will not engage recklessly and without purpose, and at 36 years old, he has at last attained the fruit of two long decades of toil.

Fightland's Jack Slack hails Pacquiao as one of the better technicians in boxing history.

"There has never been a southpaw as adept in the use of angles to create punching opportunities as Pacquiao," Slack wrote. "There might not have been any boxer to date with the same understanding and discipline in footwork."

Pacquiao’s evolution as a prizefighter has now led him to his fighting peak. He is the best he can be: an absurdly fast power puncher who throws in high volume but remains defensively responsible.

Roach recently described Pacquiao's metamorphosis to The Telegraph's Gareth Davies:

Manny’s a talented guy but we had to make some adjustments. He’s a great puncher but he had to be smart to be a champion at multiple weights. He had to learn how to box. He did that. He’s never been a big puncher at 147lb. He’s only knocked out two welterweights in his life. But Manny is better than ever, his attitude is different and I’ve never seen him work this hard. His speed is faster, his punches are harder.

Whether it is good enough to defeat Mayweather remains to be seen.

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